Sam Austin Querrey (/ˈkwɛri/;[1] born October 7, 1987) is an American professional tennis player who is currently ranked world No. 14 in men's singles by the Association of Tennis Professionals (ATP).[2] Known for his powerful serve, Querrey holds the record for consecutive service aces: 10.[3] He is also a capable doubles player, with five doubles titles and a career-high doubles ranking of world no. 23.[4]

At the 2007 Western and Southern Masters, he defeated thirteenth seed Mikhail Youzhny and advanced to the quarterfinals after defeating Argentina's Juan Mónaco, who had defeated Rafael Nadal in the previous round. He lost to no. 9 seed James Blake, but made his top 50 debut at no. 47 afterwards. At this time, Querrey was the third-ranked American behind Andy Roddick and James Blake.

Querrey played tennis for the USA at the Beijing Summer Olympics in 2008.[citation needed] He advanced to the fourth round of the US Open by defeating 14th seed Ivo Karlović of Croatia, where he was defeated in four sets by world no. 1 Rafael Nadal.

Querrey was tapped to play for the US in the Davis Cup semifinals against Spain as a replacement for James Blake, who had withdrawn citing exhaustion.[citation needed] In Querrey's first-ever Davis Cup match, he lost to world no. 1 Rafael Nadal in four sets.

Querrey next played at the ATP Tour 500 event in Washington, where he lost to top seed Andy Roddick, in the round of 16. He also played at the Cincinnati Masters losing in the third round to Lleyton Hewitt.

Querrey's year was ended prematurely by a potentially career-threatening accident in which a glass table he was sitting on collapsed, impaling his arm and requiring emergency surgery; the location of injury just missed causing nerve damage, which could have ended his tennis career.[12]

Querrey played in the 2010 Serbia Open and progressed to the final, where he faced Davis Cup teammate John Isner. Querrey defeated Isner, for his second title of the year, and his first ATP title on clay.[citation needed]

Querrey defended his title at the Farmers Classic in Los Angeles, winning a third-set tiebreaker in the quarterfinals against 2003 Australian Open finalist Rainer Schüttler, then defeating Janko Tipsarević in the semifinals, to reach his fifth final of the year.[citation needed] In the final, Querrey faced world no. 4 and 2010 Australian Open finalist Andy Murray. Querrey defeat Murray in the final.[citation needed] This was his first successful title defense, making him the first man since Andre Agassi to win two consecutive titles at this tournament.[14]

In the Australian Open, Querrey made it to the second round, where he was defeated by Bernard Tomic in four sets.[17]

Querrey reached the semifinals of the Aegon Championships, losing to Marin Čilić.[18]

Querrey progressed to the third round of Wimbledon, only to once again lose to Čilić. This was the second-longest match played in Wimbledon history, clocking in at 5 hours and 31 minutes, second only to the Isner-Mahut match at the 2010 Wimbledon Championships (11 hours and 5 minutes over 3 days).[19]

Early in the year, Querrey made the seminfinals in Auckland and San Jose. He exited in the fourth round of Indian Wells and Miami, losing to Novak Djokovic and Tomáš Berdych, respectively.

In Davis Cup competition in Boise, he won his first rubber against Viktor Troicki, but lost the deciding rubber against Djokovic, despite the fact that Djokovic suffered an ankle injury early in the match.

Querrey was eliminated in the first round in Madrid, Rome, and Wimbledon. He did not have a good summer on the North American hard-court swing and consequently slipped out of the top 20, ceding his place as top American player to his friend John Isner.

The year was not very successful, since Querrey failed to make a single final for the first time since 2011.

Querrey also struggled early in 2014, being eliminated in the first round in Brisbane and Sydney. However, he made it to the third round of the Australian Open, defeating Santiago Giraldo and Ernests Gulbis, before succumbing to Fabio Fognini.

He lost both of his ties in the Davis Cup against Great Britain in San Diego in January and was eliminated in the first round in Memphis and Delray Beach.

After failing to make it past the 2nd round of any tournament since July, Querrey started 2016 with a very strong run, reaching the semi-finals in Memphis, where he would lose to the eventual champion Kei Nishikori. The following week, Querrey reached the final at Delray Beach, where he defeated American Rajeev Ram to win his first ATP title since 2012 and return to the Top 50 of the world rankings.

At Wimbledon, Querrey faced Novak Djokovic in the 3rd round while his opponent was holding all four majors. Despite being listed as high as a 30-1 underdog,[21] Querrey upset the world No. 1 player in four sets to snap Djokovic's streak of reaching at least the quarterfinals in every Grand Slam since the 2009 French Open, and his streak of 30 consecutive Grand Slam match wins.[22] It was also Querrey's first win over a No. 1 ranked player. He then continued his successful run by defeating Nicolas Mahut to become the first American man to reach the quarterfinals of a Grand Slam since John Isner and Andy Roddick did so at the 2011 U.S. Open. In the quarterfinals, he lost to Canadian Milos Raonic in four sets.[5] Despite this defeat, the 2016 Championships marked Querrey's best ever performance at a Grand Slam.

Querrey opened 2017 in Brisbane where he fell in a Round of 32 match to Diego Schwartzman. He then won his first two matches in the first major of the season (Australian Open) before falling in straight sets to No. 1 Andy Murray. Returning to the US, he helped the US defeat Switzerland in the first round of the Davis Cup by winning his singles match against Adrien Bossel.

February saw Querrey compete in Memphis where he fell in his opening match to eventual champion Ryan Harrison. He then competed at Delray Beach where he fell in the quarterfinals to Juan Martin del Potro in straight sets. At the ATP Acapulco tournament he beat David Goffin, Dominic Thiem, and Nick Kyrgios, before defeating world No. 6 Rafael Nadal for his first career victory over the former world No. 1 player and his ninth career ATP singles title. At Wimbledon, Querrey defeated Murray in five sets to earn a spot in his first semi-final at Wimbledon. Querrey lost to Marin Čilić in the semifinals in 4 sets.[23] Furthering his success in Mexico, he won the 2017 Los Cabos Open in August, defeating Thanasi Kokkinakis in the final.

He is a quarterfinalist at the 2017 US Open. He is the first male American to reach the quarterfinals of the US Open since Andy Roddick in 2011.

Querrey plays with the Babolat AeroPro Drive GT Racquet after switching from Prince.[25] He wore Adidas apparel and shoes until the end of the 2009 season. At the start of the 2010 season, he changed his clothing sponsor to K-Swiss.[26] In February 2012, Querrey has announced that he will be joining the Babolat team and playing with their Aeropro Drive GT Plus racket.[27]